package memento.fromCSDN.manyTimes;

/**
 * 实现多次撤销
 */
public class Client {
    private static int index = -1; //定义一个索引来记录当前状态所在位置
    private static MementoCaretaker mc = new MementoCaretaker();

    public static void main(String args[]) {
        Chessman chess = new Chessman("车",1,1);
        play(chess);
        chess.setY(4);
        play(chess);
        chess.setX(5);
        play(chess);
        undo(chess,index);
        undo(chess,index);
        redo(chess,index);
        redo(chess,index);
    }

    //下棋
    public static void play(Chessman chess) {
        mc.setMemento(chess.save()); //保存备忘录
        index ++;
        System.out.println("棋子" + chess.getLabel() + "当前位置为：" + "第" + chess.getX() + "行" + "第" + chess.getY() + "列。");
    }

    //悔棋
    public static void undo(Chessman chess,int i) {
        System.out.println("******悔棋******");
        index --;
        chess.restore(mc.getMemento(i-1)); //撤销到上一个备忘录
        System.out.println("棋子" + chess.getLabel() + "当前位置为：" + "第" + chess.getX() + "行" + "第" + chess.getY() + "列。");
    }

    //撤销悔棋
    public static void redo(Chessman chess,int i) {
        System.out.println("******撤销悔棋******");
        index ++;
        chess.restore(mc.getMemento(i+1)); //恢复到下一个备忘录
        System.out.println("棋子" + chess.getLabel() + "当前位置为：" + "第" + chess.getX() + "行" + "第" + chess.getY() + "列。");
    }
}
